This invention relates to a device for changing the temperature of material placed therein and more particularly to such a device which can be used to refrigerate or heat medical specimens or foodstuffs or beverages after placement therein by medical personnel in the case of medical specimens that must be refrigerated or cooled or by other personnel in the case of foodstuffs or beverages.
It is often necessary or highly desirable to refrigerate certain medical specimens such as spinal fluid, blood and other body fluids, pending the testing thereof. If refrigerated, the time periods during which tests must be completed are extended.
Heretofore, there has been no convenient way to effect such refrigeration.
It is desirable also to be able to refrigerate or heat such items as beverages and foodstuffs when desired.
Accordingly, it is an important object of the invention to provide a self-refrigerating or self-heating device for automatically refrigerating or heating materials placed therein by medical or other personnel.
It is another object to provide such a device that is of simple, inexpensive construction and is simple to use, and that is disposable.
The following U.S. patents were found in a search hereon:
______________________________________ U.S. Pat. No. Date Inventor ______________________________________ 3,951,127 April 20, 1976 Watson et al. 4,057,047 November 8, 1977 Gossett 4,093,424 June 6, 1978 Yoshida et al. 4,114,591 September 19, 1978 Nakagawa 4,552,190 June 11, 1985 Kuhn et al. 4,528,218 July 9, 1985 Maione ______________________________________
Watson et al. discloses a device that is said to maintain a constant temperature after activation. A first chemical is within a container and actuation is accomplished by adding a second chemical to the container through a valve. The device is intended for use as a warm baby mattress, a warm blanket or a hot water bottle substitute, for example.
Gossett teaches a thermal pack comprising three bags, two of which are of the same size and contain chemicals. The third bag contains water and is rupturable by by manual pressure, allowing the water to react with the chemicals to provide either an increase or a decrease in temperature. The pack is flexible so that it can conform to the surface being treated.
Yoshida et al. relates to a thermogenic composition that generates a large amount of heat merely through contact with air, without the addition of water. The composition is kept in a case and is exposed to oxygen when the case is perforated by a needle, when a cover film is peeled off, when a pull-tab is removed, or when a screw-type perforating mechanism is used. Suggested uses are for heating many items exterior to the case.
Nakagawa relates to an exothermic metallic composition for a body warmer. The composition is contained in a porous bag to be applied to a portion of a human body.
Kuhn et al. discloses a flexible heat pad which is actuated electrochemically.
Maione discloses a disposable device for self-heating or self-cooling drinks or other foodstuffs by an exothermic or an endothermic reaction. The device has a outer diaphragm 7, a room 8 for a solid reactant and an inner breaker, a room 9 for a liquid reactant and an inner breaker and a room 10 for liquid or solid foodstuff. After the liquid or solid foodstuff is introduced into room 10, room 10 is heat sealed with a peelable diaphragm 3, which assures a long conservation of the food product in room 10 and is removed before using the contents of room 10. Thus, Maione is limited to pre-packaged foodstuff.
Maione is the only prior art example of a device which involves heating or cooling something which is within the device.
A self-refrigerating specimen container in accordance with the invention prevents specimen deterioration and possible false results from a deteriorated specimen. The invention also avoids having to obtain a second specimen because a first specimen has become spoiled. At present, it is common practice to refrigerate specimens in pans of ice, but that practice has numerous disadvantages, among which are the time wasted procuring an ice holding container and a few pounds of ice, the difficulty experienced with specimen labels in ice pans, in which the ice and melted ice commonly blur the label information or cause the specimen labels to fall off the specimen containers.
It is therefore an additional object of the invention to provide a self-refrigerating device for medical specimens, which device overcomes the disadvantages enumerated in the preceding paragraph.
The foregoing and other objects and advantages will appear hereinafter.